This “Cocked Hat” was built in Boston at the George M. Guild Co. in 1861, the 10th such unit made at the Guild shop, back when Boston was the piano-manufacturing capital of the nation. Its retail value then was $1,000. And now? About $100,000, yet somehow the man who has owned the instrument for the past four decades had no idea until recently that it was worth so much.

That man, Ron Hansford, a retired ballet dancer and instructor who bought this piano in 1971 in his hometown of St. Louis and stored it at his mother’s house there, has had it restored and is having it shipped to his home on Langston Hughes Place in Harlem.

“I figured it was poetic justice to have it relocated to Harlem, the home of one of the greatest musical periods in our country’s history, and to the block named for one of the most creative and important artistic minds of a generation,” Hansford says. “I don’t know much about the piano’s life before it came into my life, but I know that this location is a good, almost spiritual home for it.”

That summer of ’71, Hansford, then a 17-year-old high school senior who had recently begun collecting vinyl records, had gone to the home of another St. Louis record collector to purchase music. That’s where he stumbled upon this piano.

“I saw they were into collecting pianos too, mostly player pianos,” Hansford says of his fellow record-collector. “But then I saw this one. I was smitten. It was beautiful and I had to have it, never mind that I didn’t play piano. I’d had a small electrical organ as a child, but that was it.”

Hansford says he paid $700 for old No. 10 and had it delivered to his mother’s house across town.

Wade Payne for The Boston Globe/VIA AP

Details of the restored piano.

“I wanted to do something special with it,” he said. “And I’ve said that ever since — the entire 42 years. But it was only a couple years ago that I finally decided to have it looked at and find out what this piano’s story was.”

Hansford, retired from ballet for several years and living in Harlem, began to research reputable piano restorers and appraisers. And every expert he encountered pointed him to Stinnett, proprietor of the Antique Piano Shop in Friendsville, Tenn.

The first thing Stinnett did after agreeing to work with Hansford was travel to St. Louis to see the piano for himself.

“I was blown away, simply amazed,” Stinnett says. “It was the real deal, authentic. The thing that made these pianos so rare is they were hybrids of two different styles — traditional grands and squares. But it was in rough shape and needed a lot of work.”

And so he gave it a lot of work. Stinnett and his team spent 18 months disassembling the piano and reconditioning or rebuilding every element.

Wade Payne for The Boston Globe/VIA AP

Underneath the “Cocked Hat.”

“Thankfully,” he says, “we didn’t have to rebuild as much as you might imagine. It was much more slow, methodical restoration work — stripping and resealing the wood, shaving other parts, restoring the original George M. Guild stamp, conditioning moving parts. So we were able to preserve many of the original elements.”

In an appraisal and authentication letter to Hansford, Stinnett wrote:

This is to certify authenticity of this Vintage George Guild “Cocked Hat” Style Grand Piano, Serial #10. Our archives state that George Guild began building pianos in Boston in 1861, so this extremely low and early serial number would place your piano at circa 1861, making it the earliest and most historically important instrument by Guild we know of to survive.

The instrument is made of Brazilian Rosewood and is of the Rococo Victorian style. The instrument is a “Cocked Hat” style piano, a short-lived 19th Century hybrid of the square piano and the grand piano. Very few of these “Cocked Hat’’ pianos were ever built, and they are exceedingly rare today. The piano has been restored and refinished to like-new condition, inside and out, and the restoration was done with a full historical perspective in mind. The original ivory keys were preserved in restoration.

This piano is likely the only one of its kind in the world today. We estimate replacement value of this particular instrument to be approximately $90,000-$100,000 in today’s market with value appreciating over time.

Of the piano’s current value, Hansford could only stutter an incredulous “Who knew?”

There is one mystery left to this piano that Hansford says he’d love to know. Where was it from its 1861 birth in Boston until he found it as a teenager in the Midwest?

“I have no idea,” he says with a chuckle. “And I’m not sure the person I bought it from knew either before they came to own it.”